For anti-icing, supercooled water should be removed before frozen onto the contact surface. We use a hydrophobic coating for anti-icing and introduce the static- and dynamic-evaluation methods. The methods describe the contact surface between the hydrophobic surface and a supercooled-water droplet. The former is based on the contact angle, and the latter is based on the sliding angle. The temperature factor is included in these models to evaluate the hydrophobic coating under the supercooled conditions. Four hydrophobic coatings are experimentally evaluated based on the static- and dynamic evaluation methods: C1-C3 (commercial fluorocarbon coatings), and Jaxa coating (original fluorocarbon coating). These are evaluated under the supercooled conditions of -10 to 0 °C. The static-evaluation shows variations in the temperature. However, change in the contact angle by the temperature is relatively small compared to that of the sliding angle for the dynamic evaluation. Only C3 and Jaxa coatings are tolerant to the sliding angle under the supercooled conditions tested. The dynamic evaluation shows that even if the coating is hydrophobic, the dynamic evaluation should be included to understand the characteristic of removal for a supercooled-water droplet.

In-flight icing for aircraft is a large concern for all those involved in aircraft operations. Generally, an electric heater has been used to prevent in-flight icing. A hybrid anti-icing system combining ice-phobic coating and electrothermal heating (ICE-WIPS) has been proposed by the Japan Aerospace Exploration Agency (JAXA) to reduce the power consumption in the heating unit. In order to validate the effectiveness of ICE-WIPS, validation and demonstration tests are conducted using icing wind tunnels at the Kanagawa Institute of Technology (KAIT) and at the Icing Research Tunnel in the NASA Glenn Research Center. Using a NACA0012 airfoil as a test model, ICE-WIPS demonstrates substantial reduction in power consumption as compared to the existing heating system. The reduction depends on the in-flight icing conditions; more than a 70% reduction is achieved at a liquid-water content (LWC) of 0.6 g/m3 and a median-volume diameter (MVD) of 15 μm at 75 m/s with zero angle of attack. In wet-icing conditions, more than a 30% reduction in power is achieved.

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Polytetrafluoroethylene (PTFE) chemically repels water droplets due to the nature of fluorine substituents. This paper presents an experimental study on the impact of PTFE particle size and temperature on the hydrophobicity of a surface. The present study analyzes hydrophobicity due to both the chemical properties of PTFE and the microstructure created by PTFE particles. Herein, studies of the contact angle and the sliding angle of these surfaces are described in supercooled-water conditions ranging from −10 to 0 °C. From the equations governing the surface tension and sliding angle of a droplet on a superhydrophobic surface, it is found that particle size has a much greater effect on hydrophobicity than temperature. An increase in the PTFE particle size greatly reduces the sliding angle, which indicates a lower amount of energy required to remove the droplet from the surface.

Chemicals have multiple effects in biological systems. Because their on-target effects dominate the output, their off-target effects are often overlooked and can sometimes cause dangerous adverse events. Recently, we developed a novel decomposition profile data analysis method, orthogonal linear separation analysis (OLSA), to analyse multiple effects. In this study, we tested whether OLSA identified the ability of drugs to induce endoplasmic reticulum (ER) stress as a previously unrecognized factor. After analysing the transcriptome profiles of MCF7 cells treated with different chemicals, we focused on a vector characterized by well-known ER stress inducers, such as ciclosporin A. We selected five drugs predicted to be unrecognized ER stress inducers, based on their inducing ability scores derived from OLSA. These drugs actually induced X-box binding protein 1 splicing, an indicator of ER stress, in MCF7 cells in a concentration-dependent manner. Two structurally different representatives of the five test compounds exhibited similar results in HepG2 and HuH7 cells, but not in PXB primary hepatocytes derived from human-liver chimeric mice. These results indicate that our decomposition strategy using OLSA uncovered the ER stress-inducing ability of drugs as an unrecognized effect, the manifestation of which depended on the background of the cells. Small compounds have the capacity to interact with multiple cellular proteins, thereby mediating multiple effects depending on their exposure to interacting proteins. It is quite difficult to identify the full range of effects of a new chemical, even for its developers, and some factors may be unrecognized. Even approved drugs show off-target effects that are often unrecognized during drug development, and which can lead to adverse reactions including lethal effects. For instance, astemizole has been withdrawn from the market in most countries because it causes a fatal side effect, cardiac arrhythmia 1,2 , by blocking the human Ether-ago go Related Gene potassium channel, thereby causing QT interval prolongation and torsade de pointes. However, we should not be too negative about unrecognized effects of small compounds, because identification of these can lead to drug repurposing. For example, memantine was synthesized in 1968 as a derivative of amantadine, an anti-influenza agent. Recently, it was revealed that this anti-influenza agent is also an antagonist for the N-methyl-D-aspartate receptor, and the drug has become a medication for dementia 3. Thus, the important question is how such unrecognized effects of chemicals can be identified. Profile data analysis is quite useful in addressing this issue. Although the terminology sometimes varies between contexts, the method is a type of multivariate analysis that describes data using multiple variables and investigates the relationship between data with high robustness and detection power by sharing information about the structure of the data 4. Data from "omics" analysis, which converts biological information of a specim...

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In recent years, the battery driven tram car (wireless tram) is researched and developed. The important information for the system is the battery state-of-charge (SOC) during the tram operation. SOC can be estimated by calculating battery open-circuit-voltage (OCV). In this paper, on-line SOC estimation by equivalent circuit in the current fluctuating condition is described. The experimental result will be also shown.

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